generally the population progresses on their on terms.
if youre comfortable in the air with threes, start carving off the lip of the jump and letting the carve set your spin. once youre able to carve threes off any jump, start dipping your shoulder (left shoulder if you spin left, right shoulder if you spin right) and that should set you into the cork.
spot your landing as it comes around and put your feet down.
if youre able to carve a three off the jump comfortably, youll be able to cork three.